1. Field of Invention
The present invention relates in general to the field of artificial insemination of mammals. More particularly, the present invention relates to an apparatus and a method useful for non-surgical embryo transfer and artificial insemination of mammals. Specifically, a preferred embodiment of the present invention relates to transfer of fluid medium comprising semen, a fluid medium containing embryos or some medicinal fluid into the uterus of a female mammal such as a sow.
2. Discussion of the Related Art
In recent years, effective application of artificial impregnation including artificial insemination and non-surgical embryo transfer has established a proven method for improving the production of domestic livestock. Generally, such techniques enhanced the ability to selectively breed a single genetically superior male for production traits with a large number of females. Selective breeding of course allows for livestock with improved genetic traits for production. Artificial insemination techniques also decrease the chance of diseases and physical injury that can be associated with the natural breeding process. As a result of these and other advantages, the use of artificial insemination and non-surgical embryo transfer have become a widespread technique in the management of many species of domestic livestock. One of the non-surgical embryo transfer systems described in the prior art, involves inserting a tubular instrument into the cervix of a recipient female, and then depositing 10-12 milliliters of liquid medium containing embryos into and through the instrument, the objective being to deposit the embryos in the uterus. However, other procedures have several drawbacks. First, there is no way to determine whether the instrument has been inserted far enough into the cervix so that its forward end is adjacent to the body of the uterus. As a result, instances where the forward end of the instrument remains lodged within the cervix, the embryos may never reach the uterus to initiate pregnancy, and thus pregnancy rate may be reduced. As a result of the aforementioned problems, the pregnancy rate or liter size in embryo-transfer may be reduced. This results in annual monetary losses due to the cost of maintaining the non-pregnant recipient animals.
Other conventional artificial insemination (AI) techniques in the industry for some species may result in reduced pregnancy rate or litter size because not enough sperm cells were deposited into the uterus. To compensate for this and to maximize pregnancy rate or liter size, larger numbers of sperm cells are introduced than may be necessary if the entire insemination dose was deposited into the uterus. This is also due to the difficulty associated with passing a conventional straight AI device through the cervix of some species. The reason why the passageway of the cervix is difficult to navigate in most mammalian species is that the inside of the cervix has ridged folds of tissue which block straight entry. These folds need to be circumvented to penetrate the cervical passageway and reach the uterine body. Therefore, there is a need for an improved system for affecting the non-surgical transfer of embryos into recipient animals and artificial insemination, particularly those species having a cervix of the type, which is difficult to navigate, such as swine, sheep, and goats.
The present invention relates to an apparatus and a method useful for non-surgical impregnation of mammals. Specifically, a preferred embodiment for the present invention relates to transfer of fluid medium comprising semen or a fluid medium containing embryos into the uterus of an animal.
In accordance with one aspect of the invention, an apparatus for depositing semen into a uterus of a mammal includes a conical chamber that has a plurality of perforations. An exterior spiral formation of the chamber is configured for penetrating the spiral cervical passageway, which provides the entrance to the uterine body. A sheath having a frusto-conical rearward end extends axially from an aft end of the conical chamber. A fluid receptacle or semen or embryo packaging unit is coupled to a rearward end of the sheath. A tubular depositing chamber extends axially from the conical chamber to a position beyond a fore end of the conical chamber. The tubular depositing chamber has an end that has an aperture to permit the flow of semen or embryos out of the depositing chamber and into the uterus. An embryo or semen packaging unit is coupled to the rearward end of the depositing chamber.
In accordance with another aspect of the invention, a method of depositing semen or embryos into the uterus of a mammal includes the steps of: a) inserting a conical chamber having a fore end and an exterior spiral formation into cervix of a mammal, b) securing the conical chamber within walls of the cervix, c) projecting a depositing chamber through an interior portion of the conical chamber, d) moving the depositing chamber transcervically to a semen or embryo release position for release of semen or embryos in the uterus, and e) securing a semen or embryo packaging unit to the depositing member to deposit semen or embryos in the uterus.
Another benefit of the present invention is that for artificial insemination directly into the uterus of some species, the insemination time is reduced. Thus, labor costs are minimized. Still another benefit is that the device is inserted while the animal is standing so breeders can safely more quickly delivering the fluid to a multitude of animals and thus be more efficient.
These and other aspects and objects of the present invention will be better appreciated and understood when considered in conjunction with the following description and the accompanying drawings. It should be understood, however, that the following description, while indicating preferred embodiments of the present invention, is given by way of illustration and not of limitation. Many changes and modifications may be made within the scope of the present invention without departing from the spirit thereof, and the invention includes all such modifications.